It wasn't a mouse. Nor a chipmunk. Not really a squirrel. Consultation with the web and Moose Hill Audubon center, and we determined it was a flying squirrel! What's next? A moose?

We put it in our extra mouse cage, but it wasn't really happy. We let it go later that day.

Unfortunately, we kept trapping and re-trapping squirrels. We figured they were re-trapped because we started marking them with magic marker (which itself was a bit of a trick), and got a repeat offender.

Then they learned how to get the bait out of the little trap without getting trapped, and one learned how to get itself out of the trap (and thus loose in the house!) So we bought a new bigger trap that could hold multiple squirrels, hoping to catch many at once. This one works by having a one-way door that the squirrels push open to get in but then can't push open to get back out.

However, it appeared that they could not get into this trap! We think the push-open doors have too strong a spring, so they treat the door like a wall.

So we resorted to a squirrel training program. First, we tied the doors open with string, and put bait inside. The bait was taken, so we knew we still had squirrels (or, I suppose, mice). Then we put the trap back in unadulterated. No squirrels.

The next trick was to tie the door ajar so the squirrel would have pressure on its back as it squirmed through the space, but not have to work so hard against the spring. This time we got one. It had apparently decided that the trap would make a really nice nest base, so it had evidently made several trips inside, bringing in insulation and shredded boxes as nesting material, and was asleep in the nest when we checked on the trap in the morning. We quick untied the doors so they'd stay shut and brought it downstairs.

We tied the door a little lower the next time, like doing the limbo, and caught another squirrel while we were near enough to hear it scrabbling around. It was having difficulty finding the way out, poking its nose in all the different corners, so again we untied the doors and took it away for release. So much for the many squirrels in one trap idea.

We'd been marking them with magic marker, but this was a headache to apply: you set the trap next to the little mesh cage we made and hold them together (one person stepping on the trap works well while the other does the hand-work). Then push the trap door down with the chopstick fed through the mesh and startle the squirrel so it rushes into the mesh. Drop the shingle through the hole in the top and the squirrel is now caged in a tiny space. Then you poke the magic marker tip through the mesh (we enlarged some of the holes for this purpose) and hope the squirrel squirms around enough to get some stripes or dots on its back.

Marker pen would be really difficult to use through the much larger trap, with them being able to dodge around in the larger area. So we bought livestock marking dye. It's hard to get this in a small enough quantity: they think you are marking a thousand cows! It still turns out to be somewhat tricky to get the little buggers sprayed. We've been trying to spray them on the tail so we can try to spray them on the back after we get the first return customer, but I had trouble with aim and really plastered one on the back as well as the tail.

We've continued to set the small trap, and have gotten a couple that way too, using the old release-to-mesh-cage plan, but the sprayer instead of markers.

[Update, later: The spray turned out not to last, so we had to go back to markers anyway, coaxing the squirrels into the small cage to do the marking.]

Closeups of the next big-trap squirrel, still in the trap (pre-marking), hanging onto the side. You can see the white underbelly and the "wing" skin in the second picture.